Joost van der Waal from Isoleerbewust insulates Rotterdam homes with ecological materials

After ten years of working behind the computer as an architect, it was time for change for Joost van der Waal. "During research into biobased building, I discovered the capability of ecological materials to store CO2. Especially with natural insulation materials you can make a lot of ecological gains. We should do that, I told my employer. But he preferred to continue designing new architecture."

Joost decided to take matters into his own hands and to start his first insulation project in his spare time. After six months, he quit his office job for good and started his own company, Isoleerbewust.  "That was exciting because I knew very little about insulation. Until four years ago, I had never insulated a house. That first project was necessary to understand exactly what you need to do when insulating - and with ecological insulation in particular."  

Right now, wood fiber mats are a favorite, but Joost says the future lies in blowing in insulation materials. On the market are large machines with which ecological materials such as wood fiber, straw, miscanthus (elephant grass) and cellulose (old newspaper clippings) can be blown into hollow structures. "With these, you can insulate large spaces at high speed. With large volumes, the price of ecological insulation can even be cheaper than insulating with mineral materials. That's very interesting."

For Joost, who insulates mainly private homes, such a machine is still too big an investment. But in the future he hopes to be able to work with it. "The nice thing is that then you can also work with fibers from the local farmer. How cool would that be, if instead of wood fiber from Germany you work with wheat straw from farmer Piet, for example?"

Joost not only helps people by finding the right insulation for them in practice; he also shares his knowledge on his website. Inspired by Marcus Sheridan's book They ask, you answer, Joost started writing informative articles that rank well on Google. "These articles answer practical questions from people. Often not even focused on insulation, but on an underlying problem, such as: why is it cold in the house?" By writing general articles about the pros as well as the cons of different insulation materials, Joost attracts many website visitors, whom he can then warm to the ecological story. "In six months I went from 100 to 2,500 website visitors a month," he says.